So this is a new issue that has popped up for me, I thought it was maybe my home router but I have confirmed it is doing this at other hotspots as well.

My Nook HD+ does not stay connected after long periods of sleep mode (more than an hour gove or take). The WiFi symbol at the top of the screen is an empty full shape and not the number of bars for signal strength. The WiFi screen shows "disconnected". Reconnecting or turning WiFi, off and on again reconnects successfully.

I do have Avast antivirus running and a junk file cleaner and a RAM booster installed. These are the only apps I can think of that might have a setting that could limit WiFi (like a battery booster app would). There are no settings that I can see that would be causing this.

Any ideas out there? It's not a dire issue, just annoying. Otherwise I would deregister to see if that fixes it and I don't want to do that

My Nook HD+ also "shutsdown" the wifi BUT it does look like the Nook also wakes up on occassion to download updates and/or to see what's going on. Never had to do the off/on bit on the wifi to get it working. You should try disabling the 3 apps separately to see what is interferring with the wifi on your Nook.

I think that the sleep mode does turn off wifi temporarily is a "standard" on an Android. I also have an Acer A700 which has been "cyanongen'ed" & the A700 does turn off/on the wifi every "so often" (the time display doesn't display seconds).

I have a Netgear router that can use Netgear's app that has a connection mapping display. Refreshing the map, I see the A700 connected then go away; will reappear later (time doesn't matter if I hit the "refresh" or not. Looks like the Nook has a longer period of no wifi than the A700 but don't know if that is due to its modified OS.

Anyway, don't have a problem with the Nook HD+; however, did specifically look for the wifi signal display when opening the Nook & did see the blank wifi display for maybe 2 sec or so before the wifi signal display showed up.

Schwa, this has been ocurring for me, too, for the last couple of months. Coming out of sleep mode, I need to turn off wifi and turn it back on. Simple workaround, but annoying. I haven't kept records, but it seems like it only reconnects on its own fewer than the 25% of the times you are experiencing.

Per the suggestion, I uninstalled AntiVirus and Clean Master last night before putting it to sleep and charging for the night. Today it reconnected automatically when coming out of sleep mode. I'll see tomorrow if that was perhaps coincidental or causative.